Thread: new radiator for TD5, please explain

Originally Posted by Sunova

Wow this is a confusing thread. It has got me praying that I didn't do the wrong thing for my TD5's radiator. I drilled out (by hand- slow and easy) the bottom outlet pipe. The old one had a hole so my reasoning and research stated drill out the new one. The restrictor talking about is to help bring the engine up to operating temperature quicker and in our climate I didn't think it was essential. I have had it like that for about 15,000km and no problems.

I don't know the consequences of drilling out the spigots , but the tech bulletin did say this;



NOTE: The feed and return pipes, (.C. and .D. in illustrations 1 and 2), to the lower



section of the radiator have been modified. Do not attempt to open these coolant

passageways into the radiator.

Originally Posted by Sunova

The restrictor talking about is to help bring the engine up to operating temperature.

From what I have read, absolutely nothing to do with bringing the engine up to operating temperature. If you have RAVE, please read the relevant chapters. If not, get RAVE & do same. Hard going sometimes, but does explain the jigsaw puzzle that is the TD5 coolant system, Cheers, Bob

Originally Posted by bob10

Here is a photo.


What I find difficult to understand is, the two spigots are there, and looking at the drawing " COOLING SYSTEM - TD5 , Cooling system coolant flow", from RAVE, the restrictor is placed in the inlet side of the fuel cooler, coming from the bottom spigot on the radiator. Coolant from the OIL cooler outlet, via the secret hose, around the back of the engine, flows to the radiator via the top spigot. If those spigots are blanked off, surely that adversely effects coolant flow. No doubt LR engineers have engineered a solution, but what? Is there an upgraded drawing? Bob

Now you mention that no coolant could flow from the oil cooler if the spigot is blanked off it reminded me of something I read here maybe a year ago.
There was a member loosing coolant from a blanking rubber fitted where the secret hose goes.
He had no pipe around the rear of the motor and at the time many members thought it was odd.
Now I'm wondering if it had the upgraded radiator fitted and the un-needed parts removed.

Originally Posted by alien

Now you mention that no coolant could flow from the oil cooler if the spigot is blanked off it reminded me of something I read here maybe a year ago.
There was a member loosing coolant from a blanking rubber fitted where the secret hose goes.
He had no pipe around the rear of the motor and at the time many members thought it was odd.
Now I'm wondering if it had the upgraded radiator fitted and the un-needed parts removed.

I was one who thought it was odd, but I didn't have a clue about the coolant system on the TD5, still only know a little bit. I'm beginning to wonder if some of the overheating problems on the TD5 in Aus. has been caused by our [ especially our local mechanics] lack of knowledge about maintaining the engine. Just a thought, Bob

I think a description of the original radiator as per RAVE may help ,

Radiator

The 44 row , cross flow type radiator is manufactured from aluminium with moulded plastic end tanks interconnected with tubes. The bottom four rows are separate from the upper radiator and form the lower radiator for the fuel cooler. [ I believe the new, updated radiator mentioned in the Tech. bulletin does not have this separate section]

Two connections at the top of the radiator provide for the attachment of the top hose from the outlet housing and bleed pipe to the expansion tank. Three connections at the bottom of the radiator allow for the attachment of the bottom hose to the thermostat housing and the return hose from the oil cooler and feed hose to the fuel cooler.

The bottom four rows of the lower radiator are dedicated to the fuel cooler. The upper of the two connections at the bottom of the radiator receives the coolant from the oil cooler. This is fed through the four rows of the lower radiator in a dual pass and emerges at the lower connection. The dual pass lowers the coolant temp. by 24 degree C before being passed to the fuel cooler.

That is the original radiator, the modified one supplies coolant to the fuel cooler from the bottom spigot , thru a restriction, and I believe the separate bottom four row fuel cooler section has been done away with, because with the top spigot blanked, there would be no coolant flow to the fuel cooler. Exactly what happens if you drill out that blanking, I'm not sure. Bob

I thought I had conducted appropriate research before I drilled out the blank outlet. My understanding is the EU3 models had the blank and the EU2 earlier models had an open port. I rang the supplier, googled my brain off and spoke to mechanics who said that the port should be opened. Hence the port being there if required and not just a single outlet on the radiator. The original radiator was open, but then the internal compartments could be different.

PS I am only a weekend mechanic, so there is a good chance I am wrong.

Originally Posted by bob10

I think a description of the original radiator as per RAVE may help ,

Radiator

The 44 row , cross flow type radiator is manufactured from aluminium with moulded plastic end tanks interconnected with tubes. The bottom four rows are separate from the upper radiator and form the lower radiator for the fuel cooler. [ I believe the new, updated radiator mentioned in the Tech. bulletin does not have this separate section]

Two connections at the top of the radiator provide for the attachment of the top hose from the outlet housing and bleed pipe to the expansion tank. Three connections at the bottom of the radiator allow for the attachment of the bottom hose to the thermostat housing and the return hose from the oil cooler and feed hose to the fuel cooler.

The bottom four rows of the lower radiator are dedicated to the fuel cooler. The upper of the two connections at the bottom of the radiator receives the coolant from the oil cooler. This is fed through the four rows of the lower radiator in a dual pass and emerges at the lower connection. The dual pass lowers the coolant temp. by 24 degree C before being passed to the fuel cooler.

That is the original radiator, the modified one supplies coolant to the fuel cooler from the bottom spigot , thru a restriction, and I believe the separate bottom four row fuel cooler section has been done away with, because with the top spigot blanked, there would be no coolant flow to the fuel cooler. Exactly what happens if you drill out that blanking, I'm not sure. Bob

Thanks for doing the research on this Bob, it's made for a good thread.

I remember asking about the lower section being separate when I had my original radiator cleaned/roded.
I had blown into a spigot and found air only came out the other spigot.
I was told all was normal.

When I got the new one as said I drilled the lower outlets.
I can't remember if they where a separate section or into the main side tank.
I'll be doing a cooling system flush next month with a thermostat change.
I'll have to try to remember to check.

The issue is, I think, does the modified radiator have the bottom closed off section for the fuel cooler, or not. I would say no, because the blanked off top spigot suggests that. And the restriction in the bottom spigot , plus restrictor in the fuel cooler inlet, suggests pressure/ flow regulation to the fuel cooler. What would be interesting would be to find out what setup after market radiators have [ Serk, etc] At this point I would not drill out the bottom spigots, no matter what local mechanics say. Bob
L8711bu.pdf (770.4 KB, 27 view . This should be taken as gospel.